Mixed martial arts career
Gastelum was a state championship wrestler at Cibola High School in Yuma, AZ and attended North Idaho College for a year before deciding to compete in mixed martial arts (MMA) professionally. He worked as a bail bondsman prior to training MMA full-time.
He had his first professional fight in Mexico on December 11, 2010 against Jose Sanchez. He won via submission due to punches in the second round.
Following his debut, Gastelum fought in Mexico and Arizona, and amassed an undefeated professional record of 5–0. He finished every opponent he faced with 2 TKOs and 3 submissions on his record.
The Ultimate Fighter
In January 2013, it was announced that Gastelum was selected for The Ultimate Fighter: Team Jones vs. Team Sonnen. To get into the TUF house, Gastelum defeated Kito Andrews by decision. During the choosing of teams, he was picked last by Chael Sonnen for Team Sonnen.
In the quarterfinals, Gastelum would take on Collin Hart. He won the fight via first round knockout.
Ultimate Fighting Championship
Gastelum faced teammate Uriah Hall in the finals at the Ultimate Fighter 17 Finale. Gastelum won the fight via split decision to win the Ultimate Fighter 17, becoming the youngest winner in the show’s history at 21 years old and earned a UFC contract. After the victory, Gastelum announced he would be moving down a weight class to compete in the UFC ‘s welterweightdivision.
Gastelum was expected to face Paulo Thiago on August 28, 2013 at UFC Fight Night 27. However, Thiago pulled out of the bout citing a knee injury and was replaced by Brian Melancon. Gastelum finished Melancon via rear naked choke in the first round.
Gastelum faced Nico Musoke on June 28, 2014 at UFC Fight Night 44. Gastelum missed weight by one and three-quarter pounds and forfeited 20% of his fight purse to Musoke. He won the fight via unanimous decision.
Gastelum next fought Jake Ellenberger on November 15, 2014 at UFC 180 as the co-main event. He won the fight in the first round via rear-naked choke. The win also earned Gastelum his first Performance of the Night bonus award.
Gastelum next faced Tyron Woodley on January 31, 2015 at UFC 183. He missed weight by 10 lbs and was fined 30% of his fight purse which would be given to Woodley. He lost the fight via split decision. In the post-fight interview with Joe Rogan, Woodley said that he would not accept 30% of Gastelum’s purse, as him missing weight and losing was enough punishment.
Due to Gastelum not being able to make weight on two occasions while fighting in the welterweight division in the UFC, UFC president Dana White ordered Gastelum to move up to middleweight. In his return to middleweight, Gastelum faced Nate Marquardt at UFC 188 on June 13, 2015. He won the fight via TKO after Marquardt’s corner stopped the fight between the second and third round.
Gastelum was expected to face Matt Brown in a welterweight bout on November 21, 2015 at The Ultimate Fighter Latin America 2 Finale. However, Brown withdrew from the fight due to an ankle injury suffered in training. He was replaced by Neil Magny. Gastelum lost the fight by split decision. Both participants earned Fight of the Night honors.
Gastelum was expected to face Donald Cerrone at UFC 205 but, on the day of the weigh-ins, Gastelum did not make an attempt to formally make the 171 lbs limit and the bout was scrapped. This made it the third time Gastelum failed to make the 170 lb weight limit, prompting Dana White to say that he will “never let him fight at 170 again”.
Gastelum next fought Vitor Belfort on March 11, 2017 in the main event at UFC Fight Night 106. He won the fight via TKO in the first round. The win also earned Gastelum his second Performance of the Night bonus award.
Gastelum was expected to face Anderson Silva at UFC 212. However, he was pulled from the event after USADA learned he tested positive for high levels of marijuana metabolite Carboxy-Tetrahydrocannabinol (Carboxy-THC) above the 180 ng/mL allowance by the World Anti-Doping Agency (WADA) from his previous drug test for his bout against Belfort. On May 7, Gastelum’s win over Belfort was officially overturned to a “No Contest” and he was suspended 90 days (retroactive to the March 11 test date).
The bout with Anderson Silva was rescheduled and was expected to take place at a UFC Fight Night on November 25, 2017. However, Silva was pulled from the bout due to failing a USADA drug test and was replaced by Michael Bisping. Gastelum defeated Bisping by knockout in the first round. He also earned his third Performance of the Night bonus award.
In July 2018 the UFC announced that Gastelum and Robert Whittaker selected as coaches for Ultimate Fighter 28  On November 2, 2018, it was announced that Gastelum was scheduled to face Whittaker for the middleweight title on February 9, 2019 at UFC 234. However, Whittaker pulled out of the event a few hours prior and forced to undergo emergency dual surgery later in the day due to an abdominal hernia of the instestine and a twisted and collapsed bowel.
Article source: https://en.wikipedia.org/wiki/Kelvin_Gastelum